Granted Patent
Utility
US 5,340,272 · App. 07/932,069
Multi-stage centrifugal pump incorporating a sealed thrust bearing
Inventor:
Rudolf Fehlau
Patented Case
View Patent ↗
Granted: Aug 23, 1994
Filed: Aug 19, 1992
Inventor
Rudolf Fehlau
Assignee (at issue)
BW/IP International, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.